package com.hmdp.service.impl;

import com.hmdp.dto.Result;
import com.hmdp.entity.SeckillVoucher;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisIdWoker;
import com.hmdp.utils.SimpleRedisLock;
import com.hmdp.utils.UserHolder;
import com.sun.org.apache.bcel.internal.generic.NEW;
import lombok.extern.slf4j.Slf4j;
import org.springframework.aop.framework.AopContext;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.util.Collections;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Slf4j
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {
     @Resource
    private ISeckillVoucherService  seckillVoucherService;
     @Resource
     private StringRedisTemplate stringRedisTemplate;
     @Resource
     private RedisIdWoker redisIdWoker;
    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    static {
        SECKILL_SCRIPT =new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
        //配置lua语言脚本
    }
    private BlockingQueue<VoucherOrder> ordersTasks = new ArrayBlockingQueue<>(1024*1024);
    private final ExecutorService SECKILL_ORDER_EXECUTOR = Executors.newSingleThreadExecutor();
   @PostConstruct  //类初始化完毕之后 启动
   private  void init(){
       SECKILL_ORDER_EXECUTOR.submit(new VoucherOrderHandler());
   }
    private class VoucherOrderHandler implements  Runnable{

        @Override
        public void run() {
            while (true){
                try {
                    VoucherOrder voucherOrder = ordersTasks.take();
                    handleVoucherOrder(voucherOrder);
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                }
            }
        }
    }

    private void handleVoucherOrder(VoucherOrder voucherOrder) {
        Long userId = voucherOrder.getUserId();
        SimpleRedisLock lock = new SimpleRedisLock("order" + userId, stringRedisTemplate);
        boolean islock = lock.tryLock(1200);
        if (!islock) {
           log.error("不允许重复下单");
           return;
        }
        try {

           proxy.createVoucherOrder(voucherOrder);
        } finally {
            lock.unlock();
        }

    }
private IVoucherOrderService proxy;
    @Override
    @Transactional
    public Result seckillVoucher(Long voucherId) {
//        //1查询优惠卷
//        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
//
//        //2判断秒杀是否开始
//        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
//            //未开始
//            return Result.fail("秒杀未开始!");
//        }
//
//        //秒杀已经结束
//        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
//            return Result.fail("秒杀已经结束");
//        }
//        //4判断库存是否充足
//        if (voucher.getStock() < 1) {
//            return Result.fail("库存不足");
//
//        }
//        Long userId = UserHolder.getUser().getId();
//        SimpleRedisLock lock = new SimpleRedisLock("order" + userId, stringRedisTemplate);
//        boolean islock = lock.tryLock(1200);
//        if (!islock) {
//            return Result.fail("不允许重复下单");
//        }
//        try {
//            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
//            return proxy.createVoucherOrder(voucherId);
//        } finally {
//            lock.unlock();
//        }



//        Long userId = UserHolder.getUser().getId();
//        SimpleRedisLock lock = new SimpleRedisLock("order" + userId, stringRedisTemplate);
//        boolean islock = lock.tryLock(1200);
//        if (!islock) {
//            return Result.fail("不允许重复下单");
//        }
//        try {
//
//            return proxy.createVoucherOrder();
//        } finally {
//            lock.unlock();
//        }
        //获取用户
        Long userId = UserHolder.getUser().getId();
       //获取订单
        long orderId = redisIdWoker.nextId("order");
        //执行lua脚本
        Long result = stringRedisTemplate.execute(
                SECKILL_SCRIPT,
                Collections.emptyList(), //空集合
                voucherId.toString(), userId.toString(),String.valueOf(orderId)
        );
        int r = result.intValue();
        if (r !=0){
            return Result.fail(r == 1?"库存不足":"不能重复下单");

        }
        VoucherOrder voucherOrder = new VoucherOrder();

        voucherOrder.setId(orderId);

        voucherOrder.setUserId(userId);
        voucherOrder.setVoucherId(voucherId);
        ordersTasks.add(voucherOrder);
         proxy = (IVoucherOrderService) AopContext.currentProxy();

        return Result.ok(orderId);
    }
         @Transactional
         public void createVoucherOrder(VoucherOrder voucherOrder) {
             Long userId = voucherOrder.getUserId();

            int count = query().eq("user_id",userId).eq("voucher_id",voucherOrder.getVoucherId()).count();
            if (count >0 ){
                log.error("用户已经购买过一次了！");
                return  ;
            }

                 //5扣减库存
                 boolean success = seckillVoucherService.update().setSql("stock = stock -1")
                         .eq("voucher_id", voucherOrder.getVoucherId())
                         .gt("stock", 0)
                         .update();
                 if (!success) {
                     log.error("库存不足");
                     return ;

                 }
                 //6创建订单

                 save(voucherOrder);
                 //7返回订单ID

             }



}